WordPress 如何在一定字数之后添加自定义内容

    add_filter('the_content', 'zm_insert_content_after_chars_words');

    function zm_insert_content_after_chars_words($content) {

    	// 当超过1000个字符时执行此操作

    	$enable_length = 1500;

    	// 在500个字符后的第一个</p>之后插入

    	$after_character = 1500;

    	if ( is_single() && strlen( $content ) > $enable_length ) {

    		$before_content = substr( $content, 0, $after_character );

    		$after_content = substr($content, $after_character );

    		$after_content = explode( '</p>', $after_content );

    		$text = '文字内容';

    		array_splice( $after_content, 1, 0, $text );

    		$after_content = implode( '</p>', $after_content );

    		return $before_content . $after_content;

    	} else {

    		return $content;

    	}

    }